TBAB additive for inorganic CsPbI2.4Br0.6 perovskite solar cells with efficiency beyond 15%

A new additive method for inorganic perovskite solar cells (PSCs) was developed by adding tetrabutylammonium bromide (TBAB) additive into the CsPbI2.4Br0.6 precursor solution. The CsPbI2.4Br0.6-TBAB film shows high crystallinity, large grain size, low trap density, and excellent charge transport properties. Finally, the CsPbI2.4Br0.6-TBAB based PSC exhibits an impressive PCE of 15.21%, which outperforms many reported inorganic PSCs. Meanwhile, the CsPbI2.4Br0.6-TBAB based PSC could retain over 93% of the initial PCE after being stored in a N-2 glovebox for 1600 hours.